Wash oregano and rosemary, pat dry and finely chop. If desired, briefly toast the hazelnuts in a pan without fat. Peel the garlic and finely chop or press.
Put all ingredients in a blender and mix briefly. Then gradually add the sunflower oil until the desired consistency is achieved. Season to taste with salt and pepper or chilli.
Tip: A mortar can be used instead of a mixer, but in this case add the parmesan at the end so that it remains slightly coarse.
The pesto can be kept in the refrigerator for a few days and also tastes wonderful as a spread.